At this point, you have a lot of options. Immolation gives you 6-10-10-18% for damage making it the best damage increase. Fire walker gives you some extra fire resist. Totemic Mastery gives your totems damage as well as making them more tanky. Totemic Zeal will allow you to summon totems way faster - basically a free Faster Casting gem for 3 points. Shamanistic Fury is probably last resort - I wouldn't get this until 90+.

If you don't have a quality shock nova and want to use a shocking prolif trap, getting Purity of Flesh (18% life, 8% chaos res) before you get Static Blows would be a great idea.